An improved phasor based algorithm for accurate frequency measurement

A novel algorithm, called the improved phasor based algorithm (IPBA), to estimate the frequency of a power system is proposed. The IPBA calculates the difference of phase angles using transformed consecutive points of a DFT to reduce the leakage effects. The proposed algorithm has the following merits: it has higher precision than a conventional phasor based algorithm; it is immune to inter-harmonics as well as harmonics; it has simple and easy implementation; it has good performance both in steady and dynamic states. What is more, it can keep high precision in a very wide frequency deviation range, for example, 30–70 Hz for a 50 Hz system. The performance of the IPBA is compared with a phasor based algorithm through simulation experiments.